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Full text of "The manufacture and properties of iron and steel"

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nated in the first' furha'ce, is kept out of tibfe 'operation from that time forward. The second furnace, starts with a semi-purified metal and a, new and clean slag. Following is a summary of the data given by Mr. Bertrand:                       . :.), :, .s
	Metal.				Slag.		
	C	.   P	.   Si	Mn	S10a 	PaOs	!FeO>
Pigriron ........... ..... ..... ....	3.8 2.2	1.6 0.4	1.0 .05	1.0 0.5			
From first furnace ................					26.30 13.23	12.23 11.78	9.49 14.26
Prom second furnace ...... .....							
The average sulphur in the steel is .042 per cent., but all the pig-iron contained less .than .05 per cent., so there was little elimination of this element. The average phosphorus in the steel is .067 per cent. The twelve heats may be divided as follows, in their content of this element:
'1 heat
2 heats between .03 and .04
.021 per cent.
1 heat
.170 ,
Of these twelve heats one heat was so high in phosphorus that it could not be sold in America, while seven more were above the standard for American, basic steel. Attention is called to this fact to illustrate that 'on the continent of 'Europe the specifications on structural steel are in no manner as severe as in America. In this country a charge known to contain .17 per cent, of phosphorus would be remelted and never spoken of as steel. On the other side it needs only to pass certain physical tests and it will he accepted .by Lloyds, in. England, or by a hundred engineers on the Continent. Later results on Kladno practice have been given by Mr. Harts-horne,* who has kindly given me the original reports. The pig-iron was nearly all .molten and carried about 1.5 per cent, of phosphorus, while the average metal from the primary furnace .ran as follows in phosphorus: :                     . . ... ,v
* Trans. A. I, M. E,, Feb. 1900.                              :            ;